Electric pressing iron with ready light and pop-up power switch

ABSTRACT

An iron includes a soleplate heated by a heating element, a temperature sensor disposed to measure the temperature of the soleplate, mechanical user controls for adjusting the current temperature selection, and a ready lamp adapted to indicate when the soleplate is at the currently selected temperature.

RELATED APPLICATIONS

The present application is a continuation-in-part of U.S. patent application Ser. No. 10/959,493, filed Oct. 5, 2004, entitled ELECTRIC PRESSING IRON WITH USER INTERFACE and is related to U.S. patent application Ser. No. 10/961,903 filed Oct. 8, 2004, entitled POP-UP AUTO SHUTOFF INDICATOR FOR ELECTRIC PRESSING IRONS, assigned to the same assignee as the assignee of the present application.

BACKGROUND OF THE DISCLOSURE

1. Field of the Disclosure

The present invention relates to a user interface for the user of a steam iron.

2. Description of the Related Art

It is known in the art of steam irons to provide some indication to the user of the temperature of the iron soleplate. Such indicators are of an analog nature, usually mechanical, such as is described in Risacher, G., U.S. Pat. No. 3,488,873, for a FABRIC CONDITIONING DEVICE, issued Jan. 13, 1970.

It is also known to provide a lamp to indicate when the soleplate has reached a selected temperature, such as is described in Greco, et al., U.S. Pat. No. 4,261,120, for an ELECTRIC PRESSING IRON HAVING INDICATING READY LIGHT WITH IMPROVED SWITCH MEANS, issued Apr. 14, 1981.

A need still exists for an interface that facilitates a simple selection of the iron operating temperature and provides a clear indication as to when the soleplate is at the proper temperature for the fabric to be ironed.

A problem can arise when the operator of an iron is not present to see any indicator, such as when the operator leaves the iron on the fabric and then is distracted so as to move away from the appliance. Another problem arises when the operator stands the iron upright, walks away, and the iron tips over back onto the fabric without the operator's knowledge. This can result in a scorched fabric. It is therefore desirable to provide an iron with a mechanism that automatically shuts off the iron when no movement of the iron has been detected for a predetermined period of time and to provide some indication to the operator that such an “auto-shutoff” has occurred.

BRIEF SUMMARY OF THE DISCLOSURE

A user interface for an iron features a mechanical control for adjusting the current temperature selection, and a ready lamp adapted to indicate when the iron is at the currently selected temperature. In one aspect of the user interface, the ready lamp is a dual-color LED. In another aspect, the ready lamp is a pair of subminature lamps, one glowing read and the other glowing green.

An iron having a soleplate heated by a heating element includes a temperature sensor disposed to measure the temperature of the soleplate, mechanical user controls for adjusting the current temperature selection, and a ready lamp adapted to indicate when the soleplate is at the currently selected temperature.

Another aspect of the invention includes a motion sensor, and a power indicator adapted to indicate that power to the heating element has been shut off after the motion detector detects no movement of the iron for a predetermined period of time.

A microcontroller is in electronic communication with the temperature sensor, the user controls, and the ready lamp, and the microcontroller is programmed to control the ready lamp to indicate when the soleplate is at the currently selected temperature.

The invention further includes a pop-up switch in electronic communication with the microcontroller. The pop-up switch controls power to the iron. A motion detector is in electronic communication with the microcontroller. The microcontroller is programmed to shut off the heating element after the motion detector detects no movement of the iron for a predetermined period of time. The microcontroller is also programmed to activate the pop-up switch to pop up after the motion detector detects no movement of the iron for a predetermined period of time.

In another aspect of the invention, the ready lamp is provided as a dual-color light emitting diode (LED). The microcontroller is programmed to control the ready lamp to indicate when the soleplate is in a first state of being at the currently selected temperature or in a second state of not being at the currently selected temperature by controlling the dual-color LED to emit at different colors for the first state and the second state. Alternatively, two tiny subminature lamps located under a single lens can provide two different colored glowing indicators, one that can glow red when the iron is heating up or cooling down, and one that can glow green when the iron has reached a selected operating temperature.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial schematic top plan view of the user interface of the invention as provided on a steam iron.

FIG. 2 depicts a generalized flowchart of the operation of the invention.

FIG. 3 is a flowchart of the startup operations of the invention.

FIG. 4 is a flowchart of the temperature selection operations of the invention.

FIG. 5 is a flowchart of the automatic shut-off operations of the invention.

FIG. 6 is a flowchart of the temperature adjustment operations of the invention.

FIG. 7 is a flowchart of the shut-down operations of the invention.

FIG. 8 is a circuit diagram of an embodiment of the invention.

FIG. 9 is an exploded view of a “pop-up” switch for use with the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 1, there is shown an iron 1 having a handle 2, the forward portion of which has a user interface. The user interface has a mechanical temperature adjusting and fabric selection control 7 that may be provided as a lever, as shown, a knob, or any other mechanical device known in the art. Other controls 3, 8 may also be provided as is known in the art of steam irons, such as for selecting water or steam to be sprayed upon the item to be ironed. A power indicator lamp 6 and a ready lamp 4 are also provided. Preferably, a “pop-up” switch 10 is provided (FIG. 9), such as described in commonly assigned U.S. patent application Ser. No. 10/961,903, attorney docket No. SUNOST-2-4461, entitled POP-UP AUTO-SHUTOFF INDICATOR FOR ELECTRIC PRESSING IRONS, filed Oct. 8, 2004, the disclosure of which is incorporated by reference herein in its entirety.

In operation, upon startup the indicated temperature setting is OFF. When the user depresses the “pop-up” switch 10, the power light 6 comes on. The user then moves the temperature control 7 to the desired temperature (e.g., SYN, meaning synthetic). As shown, it is preferable to use the names of materials to be ironed rather than actual temperatures, so as to make use of the device friendly to the user.

When the user first selects a temperature setting, a controller checks to see if the soleplate 5 is already at that temperature. If not, the temperature ready lamp 4 glows a first color, preferably red, to indicate that the proper temperature has not been reached. When the soleplate heats up or cools down to the selected temperature, the ready lamp 4 changes to a second color, preferably green, to indicate to the user that the iron 1 is ready for use. It is also preferable that one or more beeps from a speaker also be sounded to indicate to the user that the iron 1 is ready for use because the user may not wait around for the iron 1 to reach temperature. Of course, rather than utilizing a two-color lamp, one may substitute a pair of lamps of differing colors, such as red and green. Alternatively, the ready lamp 4 or the power lamp 6 may be incorporated into the pop-up switch 10.

It is preferred that the iron 1 shuts itself off after a period of inactivity. In a preferred embodiment, the “pop-up” switch is caused to “pop-up” from its depressed state and the power indicator lamp 6 is caused to flash when an “auto-shutoff” occurs. In addition, it is also desirable to provide a sonic indicator, such as for example by causing the speaker to beep at ten or twenty second intervals.

Referring to FIG. 2 there is shown an embodiment of a process that may be used to effect the workings of the invention. The process may be effected by a microprocessor and embodied in a machine-readable code stored upon a tangible medium such as is known in the art of microcomputer architecture. Alternatively, the process may be effected by hardware, or by a combination of microprocessing and hardware.

Beginning at node 30, the user turns the iron 1 on and the process flows to node 40 where the user chooses a temperature setting. At node 50 the iron monitors its movement with a motion sensor and shuts itself off if no movement is detected for a predetermined period of time. At node 60 are the operations to handle a change in temperature selection. At node 70 are the shutdown operations of the iron. FIGS. 3 through 7 show these operations in detail.

Referring to FIG. 3, the user plugs in the iron at node 31 and control flows to node 32 where the power lamp 6 is off and no energy is delivered to the heating element. Control now flows to node 33 where the user depresses the pop-up switch 10, which remains depressed. At node 34, the iron checks to see if a temperature selection has been made. If not, the iron remains unheated at node 35 and control flows through node “A” to the flowchart of FIG. 4. If the user has selected a fabric, then control flows through node “B.”

Referring to FIG. 4, control flows from the flowchart of FIG. 3 through either node “A” or “B” to node 42, representing the point at which the user has made a temperature/fabric selection with the temperature control 7. Here, the ready lamp 4 glows red and the heating element in the soleplate 5 is energized. The soleplate 5 begins to heat up.

Control now flows to node 43 where the circuit checks to see if the soleplate 5 is at the selected temperature. If not, control flows through node 44, wherein the ready light continues to glow red and power continues to be supplied to the heating element. When the soleplate 5 has reached the currently selected temperature, control flows to node 45, where the ready lamp now glows green. It should be noted that, should the user turn on the steam function of the iron, there will be a drop in the soleplate's temperature for a short period of time, which would normally cause the ready light to glow red again. Hence, it is preferable to include a steam monitoring operation at node 46 that checks to see if any temperature drop is the result of switching to steam operation. If so, the ready light is kept glowing green as the soleplate heats back up to the currently selected temperature.

Referring to FIG. 5, control flows in to node “C” from the flowchart of FIG. 4. At node 51, the iron 1 checks if there has been no movement of the iron for a predetermined period of time. In a preferred embodiment, the time is shorter if the iron is lying flat than if it is on its heel, so as to prevent burning whatever surface the iron is lying upon. Suggested times would be fifteen to sixty seconds in the lying flat position and five to thirty minutes in the heeled position.

If the user has not moved the iron for the predetermined period of time, control flows to node 52 where the power lamp 6 is shut off, the pop-up switch 10 is energized, causing it to pop up, and power to the heating element is shut off. The iron 1 remains off until the user presses the pop-up button again at node 53 and then control flows through nodes 54, 55, 56, and 57 wherein the ready light 4 glows red until the soleplate reaches the currently selected temperature, at which point the ready light 4 glows green again.

Referring to FIG. 6, control flows to node “D” from FIG. 5 to decision node 61 where the system checks if the user has changed the temperature setting. If so, control flows through nodes 62, 63, 64, and 65 wherein the ready lamp 4 glows red until the soleplate has dropped or risen to the new temperature.

FIG. 7 shows a power-down operation wherein the user again depresses the pop-up switch at node 71, causing the switch to pop back up and shut off the iron. In a preferred embodiment, a rechargeable battery may be provided to provide power to pop up the pop-up switch at node 74 should the user pull the plug at node 73.

Referring to FIG. 8, there is shown a preferred embodiment for the electrical circuit of the invention. A major problem with introducing a user interface into the handle of a steam iron is space constraints. Consider that the handle of the average steam iron is narrower than a cell phone. By utilizing multiplexing, as does this circuit, it is possible to pack a great deal of utility into a small space. To perform multiplexing, it is desirable to utilize a microcontroller that is capable of both writing and reading data on the same pin. It is also desirable that the microcontroller has built-in analog-to-digital (A/D) converter capabilities and phase-width-modulation (PWM) capabilities.

There are a number of such microcontrollers on the market, such as the PIC16C712 8-bit CMOS microcontroller sold by Microchip Technology, Inc. of Chandler, Ariz. The workings and internal architecture of the PIC16C712 are described in Microchip Technology's datasheet designated DS41106, entitled PIC16C712/716, 8-Bit CMOS Microcontrollers with A/D Converter and Capture/Compare/PWM, published 1999, the disclosures of which are incorporated by reference herein in their entirety. Further, the workings of the circuit herein are nearly identical to that described in commonly assigned U.S. patent application Ser. No. 10/959,493, Attorney Docket No. SUNOST-2-4439, filed Oct. 5, 2004, entitled ELECTRIC PRESSING IRON WITH USER INTERFACE, the disclosures of which are incorporated by reference herein in their entirety.

The basic components of the multiplexed circuit of FIG. 8 are the microcontroller 107, a temperature sensor 109, a speaker 113, a motion sensor 108, the pop-up switch 10, the temperature adjusting control 7, the heating element 111, the ready lamp 4, the power lamp 6, and the motion detector 108. The microcontroller 107 is driven by a clock signal, not shown.

The ready lamp 4 is preferably a dual-color LED, preferably red and green. In this case, the red element of the ready lamp 4 is designated “R” and the green “G.” The temperature control 7 can be a simple voltage divider circuit wherein movement of the control adjusts a variable resistor to change the voltage division. The voltage level is measured by the microcontroller 107 through one of its A/D ports (analog to digital). The temperature sensor 109 can utilize a negative temperature coefficient (NTC) sensor, as these are quite accurate. Again, the analog output is fed into an A/D port on the microcontroller 107.

As stated above, it is preferable to periodically monitor the motion sensor 108 to ensure the user hasn't walked away and forgotten to shut off the iron. The microcontroller 107 is programmed to repeatedly poll the output of the motion detector 108. The motion detector can be a rolling ball switch of known construction which acts as both attitude and motion detector. By stroking the iron over a fabric, the user causes the ball to roll back and forth, thereby repeatedly opening and closing the switch. Hence, the microcontroller will poll the motion sensor repeatedly and rapidly to detect the opening and closing of the switch. The motion detector also serves as an attitude detector, allowing the microcontroller to detect if the iron is lying flat or is on its heel.

The circuitry near the top of FIG. 8 shows the power supply. AC power is brought in through input lines ACL and ACN through the pop-up switch 10 when it is in the depressed position. A solenoid L1 allows the microcontroller 107 to pop up the pop-up switch upon application of an electrical signal. Alternatively, the user may simply press again on the pop-up switch and it will pop up back to the open circuit position. Continuing, the AC signal is brought through an RC high-pass filter 102 and converted to DC through a rectifier bridge 103. Then, zener diodes clamp the signal to 24 volts and 5 volts so as to provide a dual DC supply 104. Capacitors smooth out the DC source. The 5 volt supply is used to power the digital electronics of the iron, while the 24-volt supply is fed to the heater relay 105, which is a solenoid L2 controlled by the microcontroller through transistor Q1. When the heater solenoid L2 is closed, AC power is fed directly into the heating element 111.

As to the other components, the speaker 113 is preferably connected to a pulse width modulation output (PWM) of the microcontroller 107. This allows the speaker to be driven at a wide range of frequencies as desired. An optional temperature display 106 may be provided to display to the user the current temperature or currently selected temperature of the soleplate.

Referring to FIG. 9, there is shown a blow-up perspective view of a pop-up switch adapted for use with the present invention. Within a casing 80 is mounted a plurality of wire posts 81 that protrude outside the casing 80. The drawing shows two pairs of wire posts 81 so as to provide a double switch. A pair of conducting contacts 82 is provided that are each resiliently connected to a slider 84 by contact springs 83. Depending upward from the slider 84 is the pop-up switch button 10 b. The slider 84 is resiliently held away from the wire posts 81 by a main spring 85. As can be seen, when the pop-up switch button 10 b is depressed, the slider is depressed to bring the conducting contacts 82 in electrical contact with the wire posts 81, thereby creating a pair of closed electrical contacts. The contact springs 83 place positive pressure on the conducting contacts 82 against the wire posts 81 to ensure reliable electrical contact.

When the slider 84 is depressed, an axially springloaded cam 86 engages a pocket in the slider 84 to hold it in place and keep the conducting contacts 82 in electrical contact with the wire posts 81. The pop-up switch button 10 b thereby remains depressed. The cam 86 is held in engagement with the slider 84 by a sliding iron core element 87 slideably mounted within a bobbin 88 and resiliently pushed against the cam 86 by a cam spring 89. The cam spring 89 may be held in place by a spring mount 90, which itself may be of a ferrous material so as to enhance the strength of the magnetic field within the bobbin 88. Around the bobbin is a solenoid coil 91 (designated “L1” in FIG. 8) that provides a magnetic field upon application of a current through it leads 92. When activated, the solenoid coil 91 causes the sliding iron core element 87 to pull the cam 86 away from the slider 84, thereby causing the pop-up switch 10 to “pop-up” and break electrical contact between the wire posts 81.

The bobbin 88 may be held in place by a bobbin yoke 93 that fits to the casing 80. Alternatively, the bobbin yoke 93 may be integrally molded to the casing 80. The entire assembly is capped off and sealed by a cover piece 94.

The cam 86 will preferably engage the slider 84 in a manner that allows the user to manually cause the switch to “pop-up.” In other words, should the user wish to shut the system off manually, the user may depress the button again, causing it to return to the open circuit position. A heart-shaped cam 86 engaged with an appropriately configured slider 84 is a means of achieving this, resulting in a pushbutton switch that behaves similarly to the pushbutton on a ball point pen.

Again, note that the use of a “pop-up” switch is but one embodiment. The teachings of the invention may encompass any mechanical indicator, such as a lever or rotating knob or such, so long as the electromechanical switch has a physically moveable member, visible to the user, that may be moved from an open circuit position to a closed circuit position by the user and then moved back to the open circuit position upon activation.

While various values, scalar and otherwise, may be disclosed herein, it is to be understood that these are not exact values, but rather to be interpreted as “about” such values, unless explicitly stated otherwise.

Changes and modifications can be made by those skilled in the art to the embodiments as disclosed herein, and such examples, illustrations, and theories are for explanatory purposes and are not intended to limit the scope of the claims. Further, the abstract of this disclosure is provided for the sole purpose of complying with the rules requiring an abstract so as to allow a searcher or other reader to quickly ascertain the subject matter of the disclosures contained herein and is submitted with the express understanding that it will not be used to interpret or to limit the scope or the meaning of the claims. 

1. A user interface for an iron, comprising: a mechanical control for adjusting the current temperature selection; and a ready lamp adapted to indicate when the iron is at the currently selected temperature.
 2. The user interface of claim 1, wherein the ready lamp is a dual-color LED.
 3. The user interface of claim 1, wherein the ready lamp comprises a pair of miniature lamps.
 4. An iron, comprising: a soleplate heated by a heating element; a temperature sensor disposed to measure the temperature of the soleplate; mechanical user controls for adjusting the current temperature selection; and a ready lamp adapted to indicate when the soleplate is at the currently selected temperature.
 5. The apparatus of claim 4 wherein the ready lamp is a dual-color LED.
 6. The apparatus of claim 4, further comprising: a motion sensor; and a power indicator adapted to indicate that power to the heating element has been shut off after the motion detector detects no movement of the iron for a preselected period of time.
 7. The apparatus of claim 4, further comprising: a microcontroller in electronic communication with the temperature sensor, the user controls, and the ready lamp; and wherein the microcontroller is programmed to control the ready lamp to indicate when the soleplate is at the currently selected temperature.
 8. The apparatus of claim 7 further comprising a pop-up switch in electronic communication with the microcontroller and wherein the pop-up switch controls power to the iron.
 9. The apparatus of claim 7, further comprising: a motion detector in electronic communication with the microcontroller; and wherein the microcontroller is programmed to shut off the heating element after the motion detector detects no movement of the iron for a preselected period of time.
 10. The apparatus of claim 7 further comprising a pop-up switch in electronic communication with the microcontroller and wherein the microcontroller is programmed to activate the pop-up switch to pop up after the motion detector detects no movement of the iron for a preselected period of time.
 11. The apparatus of claim 7 wherein the ready lamp is a dual-color light emitting diode (LED) and wherein the microcontroller is programmed to control the ready lamp to indicate when the soleplate is in a first state of being at the currently selected temperature or in a second state of not being at the currently selected temperature by controlling the dual-color LED to emit at different colors for the first state and the second state.
 12. The apparatus of claim 3, wherein the ready lamp comprises a pair of differently colored miniature lamps. 